Youll need to pull the bushings, plug it and redrill. Your new hole will be part on the plug and partly in the body wood which can be tricky. The bit may want to wander. I wouldn't attempt it without a drill press. Do you have a drill press? Fwiw, most home drill presses dont have a large enough throat to reach bridge posts, so id check that first. Of course that depends on the body shape.
You sure it only needs to move back 2mm? Id maybe move it a little more than that if you need more room to adjust for intonation.